Submarine barrier and launching and arming means therefor



April 24, 1934. E. OLMO l,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARMING MEANS THEREFOR Filed March16, 1932 14 Sheets-Sheet 1 T\\\\\\\\\\\\\\\\\\\\ YT\ u\ p'i 24, 1934. E.oLMo l,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARMING MEANS 'THEREFOR Filed March16, 1932 14 Sheets-Sheet 2 W ww pri 24, 1934. E. oLMo l,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARMING MEANS THEREFOR Filed March16, 1932 14 Sheets-Sheet 3 &Emo

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Filed March 16, 1932 14 Sheets-Sheet 4 April 24, 1934. OLMO 1,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARMING MEANS THERBFOR Filed March16, 1932 14 Sheets-Sheet 5 April 24, 1934. E. OLMO 1 956333 SUBMARINEBARRIER AND LAUNCHING AND ARMING MEANS THEREFOR Filed March 16, 1952 14heets sheet 6 .FI'E. 14 35:15

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SUBMARINE BARRIER AND LAUNCHING AND ARMING MEANS THEREFOR Filed March16, 1932 14 Sheets-Sheet 8 W\ \L|\ 6 \\\\\\\\\\\\\\\\\t \\`\\\\\\\tApril 24, 1934.

SUBHARINE BARRIER AND LAUNCHING AND ARMING MEANS THEREFOR Filed March16, 1932 4 Sheets-Sheet 9 April 24, 1934. E. OLMO SUBHARINB BARRIER ANDLAUNCHING AND ARMING MEANS THEREFOR Filed March 16, 1932 14 Sheets-Sheet10 E. OLMO April 24, 1934.

SUBMARINE BARRIER AND LAUNCHING AND ARMING MEANS THEREFOR Filed March16, 1932 14 Sheets-'Sheet ll f %na April 24, 1934. OLMO 1,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARHING IEANS THEREFOR Filed March16, 1932 14 Sheets-Sheet 12 E. &ma

April 24, 1934. OLMO 1,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARMING HEANS THEREFOR Filed March16, 1932 14 Sheets-Sheet 13 x- Ja E a F:

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April 24, 1934. E. OLMO l,956,333

SUBMARINE BARRIER AND LAUNCHING AND ARIING HEARS THEREFOR Filed March16, 1932 14 Sheets-Sheet 14 /NVNTOK UNITED'` STATES PATENT OFFICESUBMARINE BARRIER AND LAUNCHING AND ARMIN G MEAN S THEREFOR Enrico Olmo,Milan, Italy Application March 16, 1932, Serial No. 599306 In italyMarch 18, 1931 1 3 Ola-inis. (CI. 114-241) The present invention relatesto subaqueous the extension of the material for the barrier albarriersagainst surface craft and especially ready initiated. againstsubmarineS, the barriers comprising: Fig. 4 is a plan view of thearrangement shown (a) A system of anchored buoys and of top in Fig. 3.ropes extending from each buoy to the next in Fig. 5 is a sideelevational View of the same sec- 60 order to secure the barrierthereto, the whole betion of the barrier as illustrated in Figs. 1, 2, 3ing arranged at a suitable depth below the water and 4 showing thecomplete extension of the barsurface; rier section with the addition ofauxiliary meshes. (b) One or more net sections being submerged Fig. 6 isa plan View of the arrangement shown to to a convenient depth, suchsections being eventuin Fig. 5.

ally suhdivided by means of lines of breaking Fig. 7 is an enlargedelevational detail of the members which permit a portion of the net tobe bobbin shown at the central part of the top of detached from the toprope and eventually from Fig. 1. the remainder of the net under theaction of a Fig. 8 is a similar view taken on right angles to 35 certainmechanical Stress; Fig. 7. 70

(c) A system of fioats servng to support the Fig. 9 is a plan View ofsaid bobbin. whole or a portion of the net, and eventually to Figs. 10,11, 12 and 13 are enlarged side elevasupport also other parts of thebarrier, which tional views of the same bobbin showing different partstoo should preferably be maintained at a positions assumed duringextention. depth of some metres below the water surface; Fig. 14 is anenlar ged side elevational View of a 75 (d) Auxiliary systems, accordingas may be slightly modified form of bobbin shown in Fig. required, ofexplosive charges, signalling or other 7 with the sole difference thatthe floats are of a apparatus which under predetermined conditionsspecial form and have attachments allowing them sha l fieet s s,exploeions Or er aCtOnS to take up different directions in such a waythat useful for war purposes. in addition to their hydrostatic upperthrust they 80 Barriers of the said type can be laid down rapmay alsohave a hydrodynamic upper thrust in I y a d eVen automatically by p y fothe presence of Currents of a certain Velocity. th r moor n a t tanchorage bu y ch Fig. 15 is a View similar to Fig. 14 but at right asare already in use for mines, with or without angles thereto. change,and of the types in which the anchor Fig, 16 a, plan of Fig, 14

one sinks to t t om. h buoys must e Figs. 17 and 18 are elevationaldetails showing an hor d With t utmOSt aecuraey With a p positionsassumed by the bobbin during extenestablished spacing between each buoyand the i n next according to the preestablished lay-out. Figs, 19, 19are an enlarged elevational detail The intermediate buoys will serve;for one of the showing the exten ding devi anchorings of each of twoadjacent barrier sec- Fi s 20 nd 21 show a barrier with net suptions. hend buOyS Will rve for anchoring ported by fioats with hydrodynamicupper thrust. one end of the barrier section adjacent to the Figs. 22and 23 shown in elevation an plan the barrier section at the end of thebarrier under buoy. The invention is clearly illustrated in the actheeffect of Currents flowing in a direction companying drawings, inwhich:- oblique to the barrier.

Fig. 1 is a side elevational View showing be- Figs. 24 and 25 inelevation and plan respectween two buoys the condition of a barrier secton tively, Figs. 26 and 27 in elevation an plan rewhen the buoys andbobbins have already been spectively, and Figs. 28 and 29 in elevationan 45 launched overb a d from t barr -l yi g p plan respectivelyillustrate different position and previous to the ,commencement of the.exassumed by another form of the bobbin illustension of the materialcarried on the bobbin trated in Figs. 14, 15, 16, 17, 18 and 19. whilein the right is seen the head O f a ba er Fgs. 30, 31, 34 and 36illustrate a particular arsection already extended. rangement for themounting of explosive charges 50 Fig. ;2 isa plan view of Fig. 1 showingthe bobbin on the bobbin as already described.

st ll carrying all the material which after exten- Fig. 35 is a planView of explosive devices eX- sion will form the barrier section betweenthe tended. two buoys. Figs. 32 and 33 in elevation and plan View illus-Fig. 3 is a side elevational viewof the same bartrate one of thepossible forms of the breaking p ,55 rier section illustrated in Figs. 1and 2 but with hooks. no

Fig. 3'? shows schematically the folding in loops efected by the formshown in Figs. 24 and 25.

Figs. 38 and 39 show in detail a particular arrangement for theformation of auxiliary moshes.

The laying of the barriers of the types abovesaid can be readily andautomatically carried out by employinlg, for each barrier sectioncomprised between two adjacent buoys, B, B one or more fioating bobbinsBT on which have been previously mounted, the nanner that will be'setout further on, the top rope Ra and the net displayng or extendingdevice hereinafter described, the net R, the explosive charges Ce, theapparatus for signalling and for other war purposes, or a portion ofsuch items, so as to allow the bobbin in the water, at the moment of itsuse, to unload into the water the parts loaded thereon in such a mannerthat the said parts can take up, in the barier, the position andfunction allotted to them. The buoys B are of the automatic anchoringtype and include anchors A operably connected to the body of each buoyby a moving rope Co.

The said bobbin may also be fitted with a roller carriage (Figs. 7 and8) having the same gauge as the roller carriages that serve forlaunching the buoys, so that the bobbin may also travel on tracksprovided on board the ship. i

The winding of the net and the mounting or all the parts that are to bearranaged on the bobbin must be carried out with the utmost care inorder to prevent the mentioned parts rrom becoming entangled with oneanother on their being unwound from the bobbin.

According to the present invention, thereore, the bundle of the wiresforming the net R, and the various ropes for attachment to the floatsmay be previously arranged in a continuous or discontinuous protectionsheath formed, for instance by applications of a gluing material or by40' winding a paper band around them or the like. At all events,according to the invention, material employed for the sheath should besuiciently strong as long as they are dry and show but little strengthafter prolonged submersion in water, so

` that the said sheath will facilitate the regular winding-on of thebobbin and its unwinding in the water without the net becomingentangled.

In order to render easy, secure and speedy the unwinding of the net andtop rope with their above-mentioned appurtenances from the bobbin, thetop rope Ra and the net R prior to winding are so folded in loops thatthe two net ends which have got to be Secured to two different mooringand extending winohes C, after completion of the winding, come to lie atthe outer surface of the wound bobbin and at two opposite ends thereof.

According to the invention the net extending operation may be performedby means of a device in which the ropes may also serve to indicate thedistances at which the buoys must, one after the other, be launched intothe sea, and to eventually control the member serving to release thebuoy and bobbin launching apparatus. According to the invention, the netextending or displaying device comprises the ropes Fd (Figs. 1 to 4),the counterweights P, and the travelling 'ioats Gp (Figs. 1 to 13). Foreach bobbin, two counterweights P and two ropes Fd may be provided, eachof the ropes having one of its ends directly attached to thecorresponding mooring buoy B. To each rope Fd a counterweight P isdirectly attached (Fig. 11 or the counterweight is carried by a movablepulley, C, round which the rope Fal passes on its way to its fixed pointon the hood of the pulley C, the hood being carried by the traveilingfloat Gp to be hereinafter described.

This second arrangement should be used when it is desired that for agiven displacement of the counterweight there shall be a correspondingdisplacement of twice that amount of rope Fd (Fig. 22). Each of the saidropes, prior to reaching the counterweight, passes over a pulley Casupported by the cerrespondin travelling fioat and is also attached toone of the ends of the bobbin to be unwound.

The free length of each of the said ropes should be made equal toorgreater than half the distance existing between the buoys between whichthe rope is to be stretched.

In practice, at the moment when the extending of the net between twobuoys B is started, the two ouoys must be already anchored at a suitabledistance from each other and at a convenient depth. At an intermediatepoint between the two buoys there shall be the bobbin BT, with the twoends ot the net R already permanently attached each to the respectivepulley C, the pulleys C being arranged on the bobbin BT, one on one sideand the other on the other side thereof and being attached whensubmerged, and stop in the vicinity of the i latter, thereby carryingalong with them the top net ropes Ra and thus seouring the completeextension of the net R..

According to the invention the next extending device, travelling fioat,counterweight With all its appurtenances exclusive of the ropes, aremounted on the bobbin (Figs. 7- 8-9) together with all other parts thatcan be nounted on the bobbin. When the bobbin in the water thuscommences the net extending operation, the two sets making up thetravelling float and the counterweight (Fig. ll) are the first to leavethe bobbin and sink below water surface; then follow the net, thenet-supporting foats and the explosive charges which go to occupy thepreestablished pov ken of below for the next extending device will l' beoperated.

The bobbins complete with the net extension device are provided with areleaser or extension retarder So (Fig. 7), which has already beenmentioned above. In a first stage, viz. up to the moment suitable forthe extension of the net, the said releaser or retarder maintains inlocked conditions the members that hold firmly tied together the netextending device (built up by the two counterweights and fioats) and thebobbn with its appurtenances.

The working of the releaser or retarder takes place with an (eventuallyadjustable) time lag sufcient to insure that the time required for thelaunchirig of both mooring buoys and for their regular anchoring willhave elapsed.

The working of the releaser or retarder permits of slackening thebinding or any other member holding the bobbin ends and the netextension device. The net extention counterweights P (Figs. 10-11),being no longer withheld by the rope, drop to the outside and entraineach of them the corresponding pulley and travelling oat as well as thenet end connected to the pulley. From this moment, the extension of thenet is free to take place under the action of the counterweights asexplained above.

The releaser or retarder may consist, for instance, of a pin made of asalt soluble in water. The pin looks the two ends of the rope or of anyother clamping means holding the bobbin and counterweghts together up tothe moment when the salt pin, after a predetermined period of submersionin water, dissolves and releases the parts fcrmerly locked by it.

According to the invention, with a View toward effecting a betterworking of the barrier, the following auxiliary arrangement may beadopted. The rope leading to the counterweight is passed through the eyeof a thimble r- (Figs. 12 and 13). The said thimble is connected to aspot of the net head, this spotwhen the net is completely extended-beingat the same depth as the counterweight.

The thimble eye must be of such dimensione as to let the rope freelypass, but stop against the upper end of the counterweight withoutletting it pass through, in such a manner the thimble eye bears againstthe counterweight forcibly and causes a portion of the net weight to becarried on the counterweght, thus increasing the useful effect of thecounterweight if the latter happens to take up a higher lever than itshould in normal extended conditions of the net at the point where thethimble is attached. This method of connection offers the furtheradvantage that the net is maintained at a minimum distance from thecounterweight rope. Finally, this method of connection permits theutilization of the rope to which the counterweight is attached inhoisting the net when the net must be removed from the sea.

According to the invention, when it is desired to prevent a travellingfioat, along with the net extending counterweight and with the net head,from moving away from its mooring buoy under the action of externalforces, a special holding device is Secured to the net extension pulley,the holding device R, 1', being threaded on the rope that leads to thecounterweight As (Fig. 12) This holding device, while allowing thecounterweight rope to run in counterweight Sinking direction, acts insuch a manner that the movements of said rope in opposite direction arecompletely prevented or are prevented only beyond a predetermined limit.

As already mentioned, the net supporting fioats and, still more, the toprope must be maintained at a certain depth under water level (forinstance 10 metres) in order to render them less visible and in order toenable them to better withstand the wave motion, so that under theseconditions the barrier opposes no impediment to the craft passing overthe barrier, not only to surface ships but even to submarines when onlyslightly submerged.

According to the invention, in order to prevent the passage over thebarriers of larger ships and even of submarines, the ends of the cablescontrolling the ignition or' the displacement of the explosive chargesnearer to the water surface are extended above the top rope in order topermit the said explosive charges tobe laid so as to come intocontactwiththe ship. These auxiliary meshes may also be reduced to asingle auxiliary mesh Fe (Fig. 22) represented by a rope supported byauxiliary floats; this rope extends horizontally a short distance underwater level, and then one end thereof drops and connects to` at leastone explosive charge and the other end connects to the top rope or tothe floats or to another explosive charge. These cables for theauxiliary meshes must be of sufiicient strength in order that they maynot be broken by running ships. The said cables are supported andbrought near to the water level by means of auxiliary fioats Ga (Figs.22 and 23), which are Very strong but of reduced dimensions inconformity with the moderate cable weight they are intended to Carry.

The auxiliary fioats Got may also be fitted (Figs. 38 and 39) withapparatus of the kind of those already fitted to many mines,particularly to German mines, such apparatus being controlled by ahydrostatic pisten Operating when the hydrostatic pressure sinks below apredetermined limit. In this manner, when the auxiliary float reachesthe predetermined immersion for which the hydrostatic device has beenadjusted to operate, the said hydrostatic device will stop the auxiliaryfioat either at the cable or at an auxiliary cable which too leads tothe top rope.

The cables for building auxiliary meshes may be held taught by means ofcounterweghts C hanging on ropes that pass over pulleys Ca, as clearlyshown on Figs. 38 and 39, in which a suitable fioat G'r willapproximately equalize the water weight of the counterweight C andeventually of the cable.

Each auxiliary float Gr may also be utilized to support the cable Fewhich builds adjacent auxiliary meshes.

In Fig. 33 a barrier portion is illustrated along with its top rope R,net with net-supporting fioats Ga, auxiliary meshes supported by thefioats Gt and built by the rope Fe, and explosive charges N seoured tothe top rope and tied to the end of the cable Fe.

Fig. 39 illustrates a detail of the attachment of the explosive chargesto the rope Fe building the auxiliary mesh; it also diagrammaticallyshows (in the body of the float Gt supporting the auxiliary mesh) thehydrostatic piston Pi serving to stop the fioat Gt after the latter hasmoved enough to reach the desired point of submergence.

According to the invention, in order to secure a quick, easy and certainaction of the explosive charges and their movement towards the shipsthat have struck the barrier, explosive charges (provided of course withsuitable detonators like the preceding explosive charges) may bearranged back to back with, or threaded into, or incorporated in all orsome of the fioats supporting the top rope and in the travelling floatsCg (Fig. 22) care being taken, in this case, not to hinder thepossiblity for the floats to be orientated, as will be hereinaftermentioned.

According to this invention, when it is desired to easily and quicklyefiect the unwinding of the bobbin only by the employment of saidexplosive charges connected to the auxiliary meshes to form the barrierfor surface ships only, by simplifying the Construction and theunwinding of the bobbin and by permitting same to be developed' onlarger extension of space, the 'net designed to prevent the' passageof'` submersibl'e boats' will' According to the invention, in order topermit 5 the explosive charges to detach themselves *from the parteintended to support them in order to enable the explosive charges toremain fast with their control cable notwithstanding the eiect of a shipstriking the cable, suitable ing hcol-:s secure the explosive charges to'their supporting devices, the said breaking hooks being formed forinstance, by rings, so that the explosive charges can detach themselvesironi the net if they are mounted on the net, from the top rope if theyare attached to the latter, or from 'the float if they are placed backto back with the loat, or so as to detach the iloats if the explosivecharges are incorporated in the float; all this for the purpose ofallowing the explosive charge to be driven by the cable against the shipthat has run into the cable.

According to the invention, in case of a cable controlling an explosivecharge being struck by a ship, suitable breaking hooks may be employedin order to permit the detachment from the 'carrier also of the cableend that eventually is not con:

nected to an explosive charge, no matter whether this cable end is or isnot fast with a member intended to equalize the action exerted by theexplosive char-go attached to the opposite cableend.

In order to better illustrate how the explosive charges are set in placein the barrier and in order to better illustrate the connections of theexplosive charges with the other parts of the barriers and to show howthey can work in the manner above described, reference is made to Fig. 9wherein Ce are four columns of explosive charges; on suitable bobbinsmore or less than four column-s of explosive charges can be arranged atwill.

Each column of explosive charges (Fig. 34) is accommodated on the bobbinjust in the same manner as one of the fioats Gr, the external shapebeing approximately the same; in the progress of the net extendingOperations each column of explosive charges is dragged free into thewater by the unwinding of the top rope, in the same manner as thei'loats Gr are dragged. The column of explosive charges is built (Fig.34) by the superposition of two or more mines in such a manner that thetotal height of the column, inclusive of one or more iioats for thecontrol cable to be eventually arranged on the column top as will beexplained below, does not exceed the height available for the fioats.

All the said mines Ce will have the same cylindrical shape and ovoidalsection (Fig. 9). The height of the individual mines will vary accordingto the desired power of the same and there will be at least two minetypes; one type, which bears the reference En, will have a moderateheight and a slight downward driit when placed in the water, whilst theother type which is indicated at E'p will have a greater height andgreater power and a slight upward drift when placed in the water (Figs.31-34-35--36). The mine E'p will be arranged at the tcp of the column,whilst two or more other mines will form the column base. s

According to the invention, above the top mine the cable controlling thesame will be arranged, one end of the cable being permanently attachedto the upper portion of the mine E'p and the other cable-end beingattached either to a more distant point of the top rope, or to anotherexplo sive charge E'p exhibiting the features mentioned above. Thiscable is suitably connected to the top rope or to the auxiliary fioatsintended to maintain this cable higher up than the top rope, in order tobuild the auxiliary mesh described above.

To the bottom of the mine E'p a further cable, is attached, whichthrough the intermediary of a breaking hook is connected to the top ropemid way between the points where two vertical wires of the net areconnected to the top rope by means of breaking hooks. To the same pointof the top rope a small cable fee is attached by means of a breakinghook; the small cable fee is arranged like the other small cablesforming the warp of the net, but is Secured by means of breaking' hec-ksto the horizontal small cables forming the net chain. This wire fee iswound on the bobbin together with the net, but at convenient points of'the said wire explosive charges Ce are connected to the mines En formngthe bottom portion of the column (Figs. 34 and 35). When the bobbin isunwinding in the water, the unwinding net and top rcpe drag into thewater also the column of explosive charges. The mine E'p, owing to itsslight upward driit, moves in upward direction where-as the mines E rz En owing to their slight downward drift, move in downward direction ,stopat determined points accord ng to the connections established betweenthe said mines and the small cable fee (Fle. 36). These connections mustbe so established that the various mines En come, to a standstill in themiddle of a mesh of the net. The breaking hooks through which the smallcable fee is Secured to the cross wires of the net serve to. facilitatethe operation of detaching the cable fee, along with all its mines En,from the net when the net is to be disarmed.

The mine E'p is intended to be dragged against the ships that chance tostrike the auxiliary moshes above the top rope. The mines En areintended to drop, along with the net, on the submarines that chance tostrike the net and thereby detach the net from the top rope by means ofbreaking hooks RO clearly Visible in Fgs, 32 and 33.

In such cases, according to the invention, the charges of the mines E'pand Em, E n, laid on the barrier as indicated in the presentdescription, may be actuated by ring ropes permanently connected to thetop rope at the same point where the cable fee is arranged, this cableprovoking the explosion after the displacement of the mines has broughtabout the extension of a further length of firing rope. Alternately,according to the invention, the charges of the mines E'p and E n E narrangcd in the barrier in the manner described may be actuated byimpact and to this efiect the said mines are iitted with a suitablenumber of movable tubes, in retracted position which move outwardly soto project out of the mine twenty or more minutes after the bobbin hasbeen put to sea thus permitting all the manipulations for the unwindingof the net to be performed without risk.

According to the invention, in order to secure better conditions for thebarrier in the case of strong currents, a profile offering a minimumresistance to the currents is given to the fioats or to a portionthereof and at the same time the oats are provided with an attachmentdevice that will permit to the float to orientate itself in the mostfavorable manner according to the direction of the current.

It has been observed that the currents are stronger at the surface andconsequently the more important effect is that which they exert on thefioats, whereas the effect which they exert on the net proper built upof thinner wires and generally immersed at a greater depth is lessimportant. I

Yet, according to the invention, the conditions of the net under thecurrent effects are improved by a suitable shaping given to the ropesor, better, to the Wires of which the nets are made in such a manner asto considerably reduce their resistance to the Currents. On the otherhand, as the wires and ropes building up the net cannot alter theirorientation when the currents are re- Versed, so we give to the netWires and ropes a suitable elliptical section.

According to the invention, the barrier action under the action of thecurrents is further improved by giving to the longitudinal section ofthe fioats (Figs. 14 to 21) a shape corresponding to the section of anaeroplane wing which, under the action of a current, permits ofobtaining a useful dynamical eifect viz. an upward thrust in addition tothe mere hydrostatic thrust, and this with limited values of thehorizontal thrust created by the current, especially by suitablyrounding off the cross ends of the fioats. A barrier, or even a mereexplosive charge incorporated in the float, can be supported by a floatstanding under the action of a current if the fioat is shaped as justdescribed, in the same manner as a kite standing in an air current cansupport even considerable loads. Of course it Will always be necessaryfor the fioats to possess a hydrostatic thrust sufiicient to support thebarrier in the water when no current is present. According to theinvention, in order to place the fioats shaped as described into thebest conditions for reacting against the current in the said desiredmanner, the fioats will also be equipped with rudders that permit thefloat to orientate itself according as the current direction changes;they will also be equipped with an attachment system insuring such aninclination of the float that a horizontal current will strike the fioatunder a favorable angle of incidence and that will permit the mostadvantageous orientation of fioats employed for the purpose abovesaid,whatever may be the direction of the Currents. There shall be employed,for instance, an attachment system (Figs. 19- 20-21) comprising three ormore connecting links, each link being of appropriate length to securethe desired effect.

It should be pointed out that in the case of mines anchored in deepwater, even if the mine form is such as to impart a hydrodynamic upwardthrust, the downwardly pushing action of the currents generally is sogreat as to bring the explosive charges supported by the fioats too lowto permit them to be efficient against surface craft. In the case ofcontinuous barriers, with top rope and auxiliary meshes against surfacecraft as described above, Secured at their ends by fioats anchored tothe sea bottom and supported at intermediate points by auxiliary fioatshaving the above described shape adapted to hold them up under theaction of Currents, a good portion of them will maintain themselves atthe same depth allowing for a useful efiect even against surface craft.In fact there will remain the undue lowering of the mooring fioatscaused by the horizontal and vertical strains exerted on the mooringfioats and adding themselves to the horizontal and vertical strains ofthe auxiliary fioats simply attached to the barrier. Yet the top'rope orat least the center portion of the barrier will be carried upwardlytowards the water surface by the increase in the upward thrust due tothe hydrodynamic effect, and this by an amount sufiicient to compensate,for the lowering of the mooring buoys, as clearly shown in Figs. 20 to23.

By a suitable distribution of the auxiliary fioats, for instance byconcentrating on the auxiliary fioats nearest to the mooring fioats thegreatest upward thrusts that can be obtained hydrodynamically, and by arational proportioning of the thrusts of the various fioats anapproximately horizontal run of the center portion of the barrier can beobtained, this barrier portion being maintained very close to thedesired depth.

Having now particularly described and ascertained the nature of my saidinvention and in What manner the same is to be performed, I declare thatwhat I claim is:-

System and means for arming with explosive charges, for unwinding,extending and supporting subaqueous barriers, even consisting of aplurality of sections, characterized by the following:

l. A subaquecus barrier for use in war operations and the like includingin combination, a plurality of mooring buoys, a plurality of barriersections each of which is arranged between two mooring buoys, said buoysand barrier sections being adapted to be launched in the water,

each barrier section including a fioating bobbin a barrier portionnormally mounted thereon and extensible therefrom and a device forextending the barrier portion comprising two ropes each of which isconnected to adjacent mooring buoys, counterweights connected to theinner ends of the ropes and normally arranged on the bobbins, and

float supported sheaves connected to the ends of the barrier portion andover which the fioats carrying the counterweights pass.

2. A subaqueous barrier as claimed in claim 1, wherein a sheath isprovided and formed of material adapted to disintegrate when subjectedto a predetermined submersion in the Water, said sheath being arrangedabout the barrier portion on the bobbin to prevent entanglement of thecollapsible portion until after the extension thereof.

3. A subaqueous barrier in accordance with claim 1, the barrier portionbeing folded on the bobbin in loops so that the ends come to lie outsideand when pulled allow the bobbin to remain still during the extensionoperation.

4. A subaqueous barrier in accordance with claim 1, wherein the devicefor extending each barrier section alsoincludes a device embodyingretarded releasers, and clamping and binding members which form a singlesolid body of the barrier extending device and the bobbin.

5. A subaqueous barrier in accordance with claim 1, wherein a connectionlink is provided to slide along the ropes leading to the net extendingcounterweights and connected with a suitable point of the net body.

6. A subaqueous barrier in accordance with claim 1, wherein a hold-backis provided on the rope leading to a counterweight working against therope sheave so preventing either partially or wholly the lifting of thecounterweight.

7. A subaqueous barrier in accordance with claim l, wherein auxiliarymeshes are provided for use against surface craft and include supportingfioats arranged in the vicinity of the water surface, explosive chargesdetachably secured to the barrier, and cables connected with theexplosive charges and associated with the floats for controlling themovement of the explosive charges towards the craft which strikesagainst the mesh.

8. A subaqueous barrier in accordance with claim 1, wherein an auxiliarymesh is provided above each barrier section and wherein breaking hooksare provided to permit the cable forming the auxiliary mesh When struckby a ship to detach from the barrier its ends undetachabiy connectedwith the explosive charges controlled by the said cable.

9. A subaqueous barrier in accordance with claim 1, wherein the fioatsemployed in the bui1ding of the barrier are of streamline shape offeringa minimum resistance to the water Currents, and connecting devicesbetween the fioats and barrier permitting the floats to change theircourse to follow the change in the flow of the current.

10. A subaqueous barrier in accordance With claim 1, wherein the floatsemployed in the building of the barrier are each of such a shapesusceptible of giving under currents an upwardly dynamic thrust, andconnections between the floats and the barrier allowing the fioats toSteer a course in accordance With the change of flow of the current.

11. A subaqueous barrier in accordance with claim 1, wherein eachbarrier section is composed of ropes and wres with a section having along symmetrical shape with the longer 'axis perpendicular to thebarrier and of reduced resistance to current perpendicular to thebarrier.

12. A subaqueous barrier in accordance with claim 1, Wherein the fioatsfor supporting the cable building the auxiliary meshes against surfacecraft are fitted with an adjustable hydrostatic device in order to stopthe said floats at a predetermined depth belo-W the water surface.

13. A subaqueous barrier in accordance with claim 1, wherein anauxiliary barrier mesh is arranged above each barrier section andinclude cables and wherein counterweights, pulleys and floats areprovided to keep taut the cables forming the auxiliary meshes.

ENRICO OLMO.

